> A content delivery network, or content distribution network, is a geographically distributed network of proxy servers and their data centers. The goal is to provide high availability and performance by distributing the service spatially relative to end users.
Emphasis mine. CDN implies some sort of edge-hosting topology (or at least more-proximal than the main servers).
Not sure why you think CDN implies geographically distributed edge hosting. Are you getting that from Cloudflare's marketing? A company that sells a geographically distributed network?
CDN is a term used for years before Cloudflare was funded[0][1] to mean exactly that. Specifically[0]:
>CDNs act as trusted overlay networks that offer high-performance delivery of common Web objects, static data, and rich multimedia content by distributing content load among servers that are close to the clients.
and:
>CDNs first emerged in 1998 to address the fact that the Web was not designed to handle large content transmissions over long distances.
No, I'm getting it from wikipedia. It has nothing (directly) to do with Cloudflare or any other commercial interests - bittorrent is a content delivery network. You could run a private CDN. The whole purpose is moving the data to be consumed away from some centralized primary host, to nodes which are more proximal to the data consumer (either spatially, or solely in terms of bandwidth, torrent bandwidth is decoupled from the primary server). Bittorrent sort of automatically works out "proximity" by pulling from the highest bandwidth seeders. Also it's geographically distributed, providing redundancy and availability, which is arguably the more important part than proximity.
I think the criteria are that it a) delivers/distributes content b) is a network, implying multiple nodes c) lowers the latency and/or bandwidth cost of data consumption, by d) leveraging geographically distributed redundancy and/or proximity. I think the key feature is geographically distributed redundancy which differentiates it from a regular cache.
Aws clountfront is configurable to be one region or global. So would cloudfront not count as a cdn in your mind if it’s configured to be a single region?
> A content delivery network, or content distribution network, is a geographically distributed network of proxy servers and their data centers. The goal is to provide high availability and performance by distributing the service spatially relative to end users.
Emphasis mine. CDN implies some sort of edge-hosting topology (or at least more-proximal than the main servers).